Semaglutides

Background

Originally designed to treat diabetes, semaglutide has garnered significant attention in recent years for its use in weight loss treatments. The drug mimics a hormone naturally produced in the gut after meals and can trigger a number of similar responses that effectively trick the body into thinking it is full.

As of early 2025, the drug is sold under the trade names Ozempic (injection) and Rybelsus (oral) for diabetes and the name Wegovy (injections) for weight loss. All three are made by the Danish firm Novo Nordisk, though a number of similar drugs are in development.

How Does Semaglutide Work?

Semaglutide is in a class of drugs called GLP-1 agonists, which mimic the hormone GLP-1. Humans produce GLP-1 when they eat, and the hormone causes the body to produce insulin—hence its use to treat diabetes (1440 Topics: Diabetes).

However, GLP-1 also activates receptors in the nervous system, the stomach, and the gut. Each receptor triggers a different response, including slowing the passage of food through the digestive system and prompting the brain to send signals of fullness.

Semaglutide doesn’t work for everyone, but research shows that many patients with obesity were able to lose 15% of their body weight. Currently, semaglutides are only recommended for use by people with a body mass index higher than 30 or those with a BMI over 27 who also have a weight-related condition, such as high blood pressure.

Current Market

In 2005, the Food and Drug Administration approved exenatide, the first GLP-1 agonist for diabetes treatment. Health officials approved semaglutide as Ozempic in 2017 and as Rybelsus in 2019. In 2021, Wegovy became the first—and, so far, only—semaglutide approved specifically for weight loss. While the ingredients are the same, doses of semaglutide in Wegovy tend to be higher than those in Ozempic.

As of 2021, almost 2 million people in the US had prescriptions for semaglutide, a figure which tripled from 2019. High demand for Wegovy created a supply shortage, leading to the prescription of Ozempic for weight loss and creating significant concerns for people who use semaglutide for diabetes.

Some patients turned to compounding pharmacies (see 101), which can make drugs according to a doctor’s prescribed specifications (as opposed to selling premade drugs). However, the FDA warns unapproved versions of semaglutide from compounding pharmacies have not been reviewed for safety or efficacy.

Semaglutide is not the only GLP-1 agonist drug approved for diabetes treatment and weight loss. Tirzepatide, made by Eli Lilly, works similarly to semaglutide, poses similar risks, and is sold under the trade names Mounjaro (for diabetes treatment) and Zepbound (for weight loss).

In addition, many companies are developing potential future weight loss drugs—most of which involve components that act as GLP-1 RAs.

Potential Impact of Weight Loss Drugs

GLP-1 agonists tend to be expensive, and many insurance providers don’t cover them for weight loss. However, some analyses suggest there could be significant benefits if the drugs lead to a meaningful reduction in obesity.

More than 40% of adults in the US meet the criteria for obesity, a leading risk factor for osteoarthritis, diabetes, heart disease, stroke, and more. Reports suggest uptake of GLP-1 agonists may lead to widespread macroeconomic and health benefits, from billions saved in healthcare costs, to increased lifespans and productivity.